BMW debuted the new i3 coupe at the LA auto show late last year. The automaker has now announced that the car will be priced at approximately $40,000 when it goes into production later this year, making it roughly the same price as the company's incredibly popular 3-Series sedan.

The tip on pricing for the electric vehicle comes via BMW of North America CEO Ludwig Willisch. The CEO says that BMW [obviously] does not expect the electric car to be a volume model.

The “green” BMW EV is expected to qualify for the $7,500 federal tax credit. BMW also notes that it is currently waiting to hear from federal regulators if buyers who purchase the range-extended version featuring the optional engine will be able to get the $7,500 tax credit as well.

BMW is set to establish a program that will allow buyers of the pure electric vehicle to borrow a gasoline or diesel vehicle for longer trips. He did say that details are unclear at this point but the service will be offered "as an additional mobility package."

BMW currently expects most of it US dealer network, consisting 338 locations, to sell the i3 and the i8 hybrid sports car.

Minor correction. The Volt is very similar to a Prius, where the ICE can directly power the wheels. The ICE in the i3 is connected to a generator and is designed to supplement electricity from the batteries. The i3 is much more like the Fisker than the Volt.

quote: The Volt is very similar to a Prius, where the ICE can directly power the wheels

It can, but this only happens in limited situations. It's basically a serial hybrid with a clever transmission that optionally lets it operate as a parallel hybrid when cruising.

As for the i3/Volt comparison, don't forget that the i3 has the additional expense and weight of a bigger battery, so it's not clear that Volt's drivetrain is "heavy, complicated, expensive". Then you have to look at driving patterns to see if the lower gas mileage on the i3 can offset the motorcycle engine's inefficiency and lack of direct coupling.

BTW, are you sure the i3 has range limited by battery capacity? The generator would only need 20-30hp to be able to cruise at 65mph and maintain a reserve in the battery for acceleration and passing.

quote: BTW, are you sure the i3 has range limited by battery capacity?

Yes, reports are that the battery only range is 100 miles and 200 miles with the range extension. So it appears its not capable of keeping up with consumption on its own or they've chosen and extremely small fuel tank for unknown reasons.

It's not that unreasonable, as the target buyer isn't expected to drive much with the range extender. The simple engine probably gets 25MPG, so that's be 4 gallons, and a larger tank that rarely gets used is a waste of space in a compact.

Google tells me that it's a 35 hp engine, and that's enough to keep up with consumption, so I suspect you can keep filling up when the battery is depleted. If BMW is smart, they'll let the battery charge a bit with the generator so that it can be occasionally used for acceleration, rather than having only 35 hp in range extending mode.

The Volt is an extended range hybrid. There are extreme situations when the engine helps the electric motor, but that represents a minimal percentage of the time, if the owner is using it correctly (i.e. charging the battery as it should).

The Prius is a regular hybrid, which is powered mainly by the engine and assisted by the electric motor, but apart from slow speeds, it is always using the engine. That should diminish in the plug-in version, but the regular one is like that.

Think about the physics here. The engine is running creating mechanical energy. Instead of putting it directly to use as mechanical energy, the car is going to convert it to electricity (10-15% loss) and then back to mechanical energy (another 10-15% loss).

Whether that's good or bad really depends on what the car is doing. Remember, the ~30% engine efficiency is only true for a specific RPM and specific load. If the RPM or gearing or incline/decline deviates from the optimal, the engine efficiency will be worse.

In that case, the conversion losses from an engine operating 100% of the time at its most efficient RPM and loading to charge a battery, may be smaller than the reduced efficiency of an engine spending most of its time at non-optimal RPM, gearing, and loading.

The planetary gearing allows the engine to stay at its optimal RPM, regardless of vehicle speed. However it doesn't do that to generate electricity or I should say that's not its primary goal. As much of the engine power as possible must be sent to the wheels to achieve a high mpg, the leftover is sent to the generator.

The way they need to balance electric load on the generator, torque to the motor to keep the engine in its highest efficiency is an insane engineering feat. I'm surprised it ever made it past the whiteboard.

A diesel-electric train is a very different beast. The choice to decouple to engine from the drive wheels is because of the massive torque. The drivetrain loss to create a gearing that would hold up to torque demands are higher than the losses to go between mechanical and electric energy.

Interesting info about the i3's engine. In this kind of configuration (i.e. range extender can't provide power to drive the vehicle), it seems like it might make sense to have a selectable "long range" mode that would run the ICE whenever battery drain is occurring - this would minimize the chances that you are left in a position where the battery is dead and there's still fuel in the tank.

quote: The drivetrain loss to create a gearing that would hold up to torque demands are higher than the losses to go between mechanical and electric energy.

This sounds like something that may be true for specific implementations, rather than as a general rule. At the very least, it seems like something "they" would be working to rectify. I may also be completely wrong... :)

I really don't think you're right. 35hp, even after losses, is plenty for that.

A Leaf gets 102 MPGe on the highway, and that works out to 16kWh average power for the test, including inefficiencies from accelerating/braking and charging loss. A Prius only needs ~15 hp to maintain 60 MPH.

I was curious about this, so I ran an experiment this morning in my LEAF. I reset my mi/kwh as I entered the interstate and maintained my speed between 70 and 80mph. The outcome was 3.1mi/kWh. This half of my commute is overall downhill, so lets call it 3mi/kWh to keep the math simple. At 75mi/h * 1/3 kWh/mi = 25kw. The BMW engine is rated at 35hp = 26kW, so with generator losses this is just about right.

So I admit I was wrong. What boggles my mind then, is why they would rate the range with the range extender at 200mi? Why limit it so severely by the size of the fuel tank?

I really think it's just space. The idea is to not use the range extender much at all, so it's probably not very efficient (maybe 25 MPG) and they didn't want to waste more than 4-5 gal of space. Stopping for gas every 90 minutes isn't so great, but it's not terrible.

Actually you probably need more power than 35hp to maintain interstate speeds. I own a Volt which uses a 75hp engine so I have a bit of experience to reflect on this.

While 20hp is enough for highway crusing, you'll probably run into serious problems with 35hp if you are trying to climb a massive mountain. It may not be an issue depending on where you live but having that limitation is a problem. On the Volt, this problem is avoided by using mountain mode which reserves roughly about 1/2 the battery for hill climbing. GM wasn't kidding when they said they tested the Volt from Alaska to Mexico.

Also in very cold climates such as Canada which is where I live, the battery will essentially shutdown if the Volt is left in the extreme cold for hours unplugged. This happens because I don't have a plug at work. This is probably to protect the battery. I can attest trying to drive the volt on a 75hp engine alone isn't very pleasant. The engine sounds like it's really trying hard. While the i3 will likely be lighter than the volt due to amazing amounts of carbon fibre, I have a bad feeling that if only powered by the gas generator, it will likely be completely at full throttle which isn't very healthy for any gas engine.

The engine they're using, when in a moped is rated at 65hp. That is obviously peak, non-continuous, and not at all fuel efficient. I'm guessing the 35hp is the max rating for continuous. Not max fuel economy, but max continuous power.

I'm going to guess that it gets a HWY mpg rating of 30 or less on the range extender.